Synthesis of 6,6-Difluorohomopiperazines via Microwave-Assisted Detosylation­

Abstract

[1,4]-Diazepan-6-ols are easily oxidized to ketones using Swern or Dess-Martin oxidation conditions. The fluorination of these [1,4]-diazepanones with diethylaminosulfur trifluoride (DAST) affords gem-difluorohomopiperazines. Detosylation under microwave conditions represents a rapid method to access the corresponding amines in high yields.

heterocycles - sulfonamides - protecting groups - di­ethylaminosulfur trifluoride (DAST) - microwaves

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14

To prove the enantiomeric purity of 8, a tight ion-pair of 8 with (S)-(+)-ketoprofen was compared with its racemate using ¹H NMR.